CVE-2026-20809

HIGH

Windows Kernel Memory - Privilege Escalation

Title source: llm

Time-of-check time-of-use (toctou) race condition in Windows Kernel Memory allows an authorized attacker to elevate privileges locally.

CVSS v3 7.8

EPSS 0.0003

EPSS Percentile 7.4%

Attack Vector LOCAL

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Vulnrichment

Exploitation none

Automatable no

Technical Impact total

CWE

CWE-122 CWE-367

Status published

Products (31)

Microsoft/Windows 10 Version 1607 10.0.14393.0 - 10.0.14393.8783

Microsoft/Windows 10 Version 1809 10.0.17763.0 - 10.0.17763.8276

Microsoft/Windows 10 Version 21H2 10.0.19044.0 - 10.0.19044.6809

Microsoft/Windows 10 Version 22H2 10.0.19045.0 - 10.0.19045.6809

Microsoft/Windows 11 version 22H3 10.0.22631.0 - 10.0.22631.6491

Microsoft/Windows 11 Version 23H2 10.0.22631.0 - 10.0.22631.6491

Microsoft/Windows 11 Version 24H2 10.0.26100.0 - 10.0.26100.7623

Microsoft/Windows 11 Version 25H2 10.0.26200.0 - 10.0.26200.7623

Microsoft/Windows Server 2012 R2 6.3.9600.0 - 6.3.9600.22968

Microsoft/Windows Server 2012 R2 (Server Core installation) 6.3.9600.0 - 6.3.9600.22968

... and 21 more

Published Jan 13, 2026

Tracked Since Feb 18, 2026